Dropping --nacl-loader-cmd-prefix

The --nacl-loader-cmd-prefix is no longer useful in practice for injecting a
debugger after this:
https://code.google.com/p/chromium/issues/detail?id=118263
https://src.chromium.org/viewvc/chrome?view=rev&revision=230891

We should drop the switch from chromium.

BUG=350158
TEST=None
NOTRY=true

Review URL: https://codereview.chromium.org/189623003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255782 0039d316-1c4b-4281-b951-d872f2087c98

components/nacl/browser/nacl_process_host.cc

@@ -503,12 +503,6 @@ bool NaClProcessHost::LaunchSelLdr() {
     return false;
   }
 
-  CommandLine::StringType nacl_loader_prefix;
-#if defined(OS_POSIX)
-  nacl_loader_prefix = CommandLine::ForCurrentProcess()->GetSwitchValueNative(
-      switches::kNaClLoaderCmdPrefix);
-#endif  // defined(OS_POSIX)
-
   // Build command line for nacl.
 
 #if defined(OS_MACOSX)
@@ -520,8 +514,7 @@ bool NaClProcessHost::LaunchSelLdr() {
   // http://code.google.com/p/nativeclient/issues/detail?id=2043.
   int flags = ChildProcessHost::CHILD_NO_PIE;
 #elif defined(OS_LINUX)
-  int flags = nacl_loader_prefix.empty() ? ChildProcessHost::CHILD_ALLOW_SELF :
-                                           ChildProcessHost::CHILD_NORMAL;
+  int flags = ChildProcessHost::CHILD_ALLOW_SELF;
 #else
   int flags = ChildProcessHost::CHILD_NORMAL;
 #endif
@@ -576,9 +569,6 @@ bool NaClProcessHost::LaunchSelLdr() {
   if (NaClBrowser::GetDelegate()->DialogsAreSuppressed())
     cmd_line->AppendSwitch(switches::kNoErrorDialogs);
 
-  if (!nacl_loader_prefix.empty())
-    cmd_line->PrependWrapper(nacl_loader_prefix);
-
   // On Windows we might need to start the broker process to launch a new loader
 #if defined(OS_WIN)
   if (RunningOnWOW64()) {
@@ -593,7 +583,7 @@ bool NaClProcessHost::LaunchSelLdr() {
                      cmd_line.release());
   }
 #elif defined(OS_POSIX)
-  process_->Launch(nacl_loader_prefix.empty(),  // use_zygote
+  process_->Launch(true,  // use_zygote
                    base::EnvironmentMap(),
                    cmd_line.release());
 #endif

components/nacl/common/nacl_switches.cc

@@ -19,7 +19,7 @@ const char kEnableNaClDebug[]               = "enable-nacl-debug";
 // sandbox.
 const char kEnableNaClNonSfiMode[]          = "enable-nacl-nonsfi-mode";
 
-// Causes the process to run as a NativeClient broker
+// Value for --type that causes the process to run as a NativeClient broker
 // (used for launching NaCl loader processes on 64-bit Windows).
 const char kNaClBrokerProcess[]             = "nacl-broker";
 
@@ -39,11 +39,7 @@ const char kNaClGdb[]                       = "nacl-gdb";
 // GDB script to pass to the nacl-gdb debugger at startup.
 const char kNaClGdbScript[]                 = "nacl-gdb-script";
 
-// On POSIX only: the contents of this flag are prepended to the nacl-loader
-// command line. Useful values might be "valgrind" or "xterm -e gdb --args".
-const char kNaClLoaderCmdPrefix[]           = "nacl-loader-cmd-prefix";
-
-// Causes the process to run as a NativeClient loader.
+// Value for --type that causes the process to run as a NativeClient loader.
 const char kNaClLoaderProcess[]             = "nacl-loader";
 
 }  // namespace switches

components/nacl/common/nacl_switches.h

@@ -19,7 +19,6 @@ extern const char kNaClBrokerProcess[];
 extern const char kNaClDebugMask[];
 extern const char kNaClGdb[];
 extern const char kNaClGdbScript[];
-extern const char kNaClLoaderCmdPrefix[];
 extern const char kNaClLoaderProcess[];
 
 }  // namespace switches